Rubber covered flexible track



DEC. 31, 1935*. E Q MYERS 2,025,999

RUBBER COVERED FLEXIBLE TRACK Filed Jan. 25, 1932 4 Sheets-Sheet 1 Dec. 3l, 1935. E C, MYERS 2,025,999

A RUBBER COVERED FLEXIBLE TRACK Filed Jan. 25, 1952 4 sheets-sheet 2 y. .5 2g Z2 Z4 Z/ l r l f l :DI 7 I- -IL.-. wat 'T f 'J 25 y Z9 p 27 Z9 1.1. '9 Z |l. 1 -I I T 1 j T i l L J /9 22 z'z 24 z/ Dec. 31, 1935.

E. c. MYERS RUBBER COVERED FLEXIBLE TRACK Filed Jan. 25, 1932 4 SheetsTSheet 3 Dec. 3l, 1935. E, C, MYERS 2,025,999

RUBBER COVERED FLEXIBLE TRACK Filed Jan. 25, 1932 4 Sheets-Sheet 4 71,92% -Edward @Myers Patented Dec. 31, 1935 UNITED STATES PATENT OFFICE RUBBER GOVERED FLEXIBLE TRACK Edward C. Myers, Wauwatosa., Wis. Application January 25, 1932, Serial No. 588,722 2s claims. (ci. sos-1o) This invention relates to rubber covered tracks for tractors and other vehicles, conveyors and the like.

Steel tracks now in common use on crawler 5 tractors, excavators, conveyers and the like are made up on the open steel chain principle; however running on the ground and in dirt, sand, etc., soon cut out (4,000 miles maximum on tractors) due to the low resistance of steel to grinding.

Grinding cuts the hardest steel with ease,even diamonds are cut by the same process which wears these open steel tracks. Such steel tracks also wear the driving andguide members out and have proven impractical, and even if elaborately made they would not be commercial due to excessive cost. There is practically no hope of ever getting the desired mileage from steel tracks as the cause of their short life is fundamentally impossible to remove.

Further, due to faster grinding of the steel tracks as the speed increases such tracks must operate Very slowly. The speed of steel tracks is necessarily limited to about 41/2 miles per hour.

Traction cleats are also not permitted on many roads and streets and now legislatures threaten to outlaw even smooth steel shoes on streets and improved roads.

Traction belts have also been constructed of rubber and fabric but they have many limitations particularly in tensile strength and lack of positive driving means.

The object of the present invention is to overcome the difficulties just mentioned by providing a combination steel and rubber track. Steels are todays strongest materials and rubber compounds are todays best materials for resistance to abrasion and sealing for parts against dirt. In this present track steel furnishes the strength required to absorb all the pull or tension around the track driving and guide members but the power from the driving members is transmitted therefrom through the steel and thence through the rubber to the ground or roadway. 'Ihe rubber furnishes resistance to abrasion and compression to carry the load, and also protects steel parts against dirt. Unlike a steel chain it furnishes a cushion forall parts. of the machine operating on the track.

In reality the track in accordance with this in-l vention is a steel track so designed as to make covering with rubber practical and easy.

A further object of the present invention is to provide auxiliary traction cleats which may be applied to the rubber covered track or removed therefrom at will.

As an example of the present invention, one or more longitudinally extending tensioning members, such as steel braided bands or cables, and driving members are pre-coated with rubber which may be pre-vulcanized, or are coated with 5 a rubber like compound. The assembly parts are set or molded in a covering of rubber or rubber compound providing a cushioning and tread material and the entire track is then finally vulcanized. Adhesion of the rubber to the tensioning l0 members is enhanced and assured by preferably employing stranded cables in which the outer strands engage the central strand but are spaced from each other as by what may be termed a loose winding so as to provide spaces into which l5 the initial rubber coating or impregnation is securely locked. Thus thereis no question with regard to adhesion of the rubber to the parts which can readily be determined as there would be if they were not so rubber coated and impreg- 20 nated, so that before applying tread body rubber to them adhesion of the tread body to the rubber coated and impregnated parts can thereby be accomplislied as av certainty. The rubber tread is provided with openings for dirt to pass through, 25 Ventilating openings and openings for securing bolts for fastening auxiliary cleats which either engage a smooth outer surface of the tread or are formed with projections which engage transverse or other forms of grooves in the tread just 30 outside of the aforesaid driving members to which they are fastened. When the track is formed with such grooves, and the cleats are not in use the grooves provide an antiskid tread surface for the track. 35

Another example of the invention consists in molding the rubber tread body in sections with cored openings therethrough. These body sections are threaded upon the tensioning members or cables, and anchoring and driving members 40 are positioned in laterally extending cored openings therein in engagement with the tensioning members and fastening members pass through cored openings through the upper and lower faces of the sections for clamping the anchoring and 45 driving members on the tensioning members.

Further objects, features alnd advantages of my invention will be set forth in detail in the following specification in conjunction with the accompanying drawings and hereinafter claimed. 50

In the drawings,-

Figure 1 is a side elevation showing a rubber covered flexible track applied to driving wheels of a tractor in accordance with my invention.

Figure 2 is an enlarged side elevation showing 55 a portion of the track being partly in longitudinal 'section on line 2--2 of Figure 3 to show the construction of the track and its; cooperation with the wheel.

Figure 3 is a plan view partly in longitudinal section taken substantially on line 3-3 of Figure 2.

Figure 4 is a top plan view of one of the anchor members.

Figure 5 is 'a transverse sectional view taken on line 5-5 of Figure 2.

Figure 5A is an enlarged transverse sectional view of one of the cable members with its initial rubber covering.

Figure 6 is a cross sectional view similar to Figure 5 with the addition of traction cleats.

Figure '7 is a longitudinal sectional view taken on line 1-1 of Figure 6.

Figure 8 is a longitudinal sectional view, showing teeth in place of wear plates.

Figure 9 is a side elevation of a portion of track with a modied tread portion.

Figure 10 is a side elevation of the track shown in Figure 9 with the addition of traction cleats.

Figure 1l is a top plan view of one of the traction cleats shown in Figure 10.

Figure 12 is a longitudinal sectional view of a slightly modied track.

Figure 13 is a transverse sectional view taken on line I3--I3 of Figure 12.

Figure 14 is a side elevation of a track provided .with a modied type of steel traction cleat.

Figure 15 is a side elevation of a track provided with a compositon or rubber traction cleat.

Figures 16 and 17 are plan views of the tread face of a track showing other forms of tread grooves.

Figure 18 is an end view of an anchor plate with a modified type of cable clamping means.

Figure 19 is a longitudinal sectional view thereof.

Figure 20 is a side elevation of a modied form of track.

Figure 2l is a top plan view of the track shown in Figure 20.

Referring to the drawings, Figure 1 shows an endlessv rubber track I0 mounted on spaced tractor or other wheels I I in accordance with my invention. As shown in Figure 2, the rims of wheels II are provided with inner and outer side flanges I2 which engage the sides of track I0, and teeth I3 at an intermediate position between flanges I2 and either formed integral with the wheel members or, as shown, extending from plates I4 which are secured to the disk I5 of the wheel'by rivets or bolts I6 with the teeth extending through apertures in the wheel rims.

As shown in Figures 2 to 5 inclusive, track I0 has a plurality of cables I'I, four being shown which may be either formed into endless tensioned belts or have their ends butt welded with or without cable ttings as shown at I8 (Fig. 3), or otherwise secured for receiving tread body rubber. In Figure 3 a suitable form of itting swedged onto the cable is shown at I9 for securing such cable ends, and as shown these connections of the cables may be in staggered relationship in the track III although in actual'practice it is not found essential to secure ends of cables to each other. A suitable form of cable is shown in Figure 5A-in which the cable is specially wound with a wide spacing between the outer strands as compared with the spacing of the outer strands of the usual standard cables to provide space for rubber to ilow around the strands to form a lock for the rubber covering shown at 20. Thus the rubber covered cable has its individual strands coated with rubber and the rubber between the strands, in addition to the adhesion and locking features, also performs the function of a lubricant for this 5 cable tensioning member.

On cables I'I at intervals corresponding with the spacing of the sets of driving teeth I3 on Wheels I I are mounted. anchor members preferably in the form of plates 2I which provide driv- 10 ing members for the track, alone or with wearing plates or projecting teeth as hereinafter described; these plates are curved to provide spaces 2Ia for rubber cushions between the plate edges and cables While the tread is passing over lthe 15 curved rim of the wheels II. The curvature of these plates, as shown in Figure 2, providing the spaces 2| a, is very necessary to provide for rubberv cushions between the curved surfaces of thev plates or anchor members and the cables to 20 prevent undue strain, sharp bends, etc., on the cable when it is ilexed in either vertical direction. The curved plates or anchor members permit flexing without cutting or sharp bending of the cables and the safety stop" cushions of rubber provided for by the spaces 2Ia protect the cables, preventing the edges of the anchor members or plates from damaging the cables. The radius of curvature of these plates as shown, corresponds with the radius of curvature of the track as it passes around the wheel however if narrow' anchor or cross plates are employed curvature of the outside of the plate, opposite from the cables so as to follow the curvature of the wheel, is not essential. Under each anchor plate are two pairs of clamps comprising upper and lower clamp pieces 22 and 23 respectivelyv and these clamps are secured to the plates by means of end rivets 24 or the like along the cables. It is to be noted that in the longitudinally extending sec- 40 tions of the track I0 the cables, as particularly shown in Figures 2 and 3, extend in a common plane below the driving members, and around wheel I I along a corresponding radius outside of the driving members and that these cables are secured by the clamps to the driving members in a manner such that clamps do not distort the cable from straight and radius paths when the track is in position on rims of wheels and permits A the cables to be free to flex and escape any sharp bending which would soon cause them to break. Also this arrangement of clamping the driving members to the cables permits the driving members to be secured accurately at the required pitch distances so as to function properly which would be practically impossible if the clamps were arranged to distort the cables when they were fastened to them since the pitch line of the driving members for the wheel teeth must be obtained to extremely close limits,in practice the pitch 60 or spacing between the cross driving members is held within ten thousandths of an inch. Holding the pitch of the driving plates to the required close limits requires the highest grade strongest steel wire available for use in making the cable used in the track, and any looping or kinking of the cables would make accurate setting of the cross members only guess work and make the required accurate setting impossible. In fact every minute detail of this type track is extremely im- 'portant and unless correct cannot be manufactured so as to be of any service. In-the nished state this track is a one piece product with only the exceptions of removable wearing plates, therefore the rigid requirements for complete perfection thruout, failure of one part results in total loss of the unit.

Either before orjlnllowing the securing of the cables l1 and the clamps to the anchor plates 2|, tooth contact wearing plates 25 are secured to them by means of rivets or the like 28. These contact plates are so arranged that they are below the track face and either on or very close to the pitch line of thetrackf-the cables are along the pitch line or neutral axis of the track. As shown in Figure 2 these tooth contact wear plates are provided with rounded ends 21 which articulate with teeth 3 and have shoulders-21a which closely overhang the long sides of the anchor plates which will be termed the ends thereof in view of their relationship with respect to the cables. Inaddition to apertures for the tooth `contact wear plate and the clamp securing means the anchor plates are also provided with apertures 28 and corresponding apertures extending centrally through the clamps 22 and 23.

T he cables, the anchor and driving members are given a thin coating of rubber compound. In some cases a heavier coating has to be applied to the parts in which event the covering used is preferably pre-vulcanized or cured before placing them in the body of the tread.

After the rubber coverd parts are assembled, the assembly is then sent into the main rubber tread body, generally designated I0, and the complete tread is then flnally` vulcanized and the track is complete and ready for use. In molding the main tread body the rubber is cored out as shown at 29 at the ends of wear plates 25 to provide spaces for the sprocket or driving teeth |3 to enter and for dirt to pass through. 'Ihere are also cored holes 30 for access to rivets 26 which secure the wear plates 25 and likewise cored holes 3| in alignment with apertures 28 in the anchor plate 2| and the clamps 22 and 23. Thus nished, with the plurality of tensioning cables and spaced driving members mounted acro'ss them in the rubber tread body, a track is produced which is flexible longitudinally so as to travel around the spaced tractor wheels or the like but relatively transversely sti or sumciently rigid so as not to be readily thrown laterally from such wheels.

In Figures 6 and 7 the track I0 is shown provided with auxiliary traction cleats 32 having downwardly bent ground engaging ends 33. These cleats are each secured to the track by means of a pair of fiat headed and square shouldered bolts 34 passing through the cored holes 3| in the tread body and through apertures 28 in the anchor plate 28 and clamps 22 and 23, these members providing a combination cable holder and bearing for the bolts. On the outer ends of the bolts are nuts 36 for holding the cleat against the track body and lock washers 31 are preferably used to prevent the loosening of these nuts.

The track as described is provided with wear plates 25 which engage sprocket teeth on driving wheels, however as shown in Figure `8 these tooth contact wear plates may be replaced by teeth 31. As shown the track is the same in all other respects as that shown in the previous, gures of the drawings and the teeth 31 aresecured to anchor plates 2| in the same manner as the tooth contact wear plates were secured thereto. The track Ill is thus arranged to carry teeth for cooperating with sprockets of driving wheels which is preferable in some instances.

In Figure 9 the track shown is substantially of the same construction as that shown in Figure. 8 except that the outer or tread portion of the track body is provided with a. plurality of transverse grooves 38, or, as shown, with one in 5 registration under each anchor or cross plate 2| and tooth 31,` which grooves produce an antiskid tread for the track.

Under extremely bad conditions cleats 39 as shown in Figure 10, are attached by pairs of bolts 48 which serve in tension onlyy in holding the cleats in position. It will be noted that the bolts are free in the openings in the plates and clamps so as to permit the cleat to oscillate without danger of bending the bolts. These l.'

portions of the cleat when theA cleat is applied 25 as shown in Figure l0. These projections on the face of the belt are provided to avoid a gap when the belt travels around the wheels. As shown in Figure 11 these cleats 39 and cleats 32 as well are provided-*with holes 53 which register with the holes in the track to permit dirt to pass through.

In the tracks arranged to carry teeth 31, cored out openings 29 for teeth of the driving Wheels to enter are not essential but are preferably provided for dirt to pass through regardless of the type of tooth used. While it is preferable lto mold the rubber body tread on the assembly in one operation, the formof track shown in Figures 9 and 10 lends itself to molding the body .40

in a plurality of sections as may be more convenient in that smaller, or shorter mold sections are required. In molding the track in sections, such sections are arranged to extend to grooves 38 under teeth 31 so that when the complete track is molded the wearing tread portion of the track will be substantially uniform.

In Figure 10 a portion of a suitable type of sprocket wheel 43 is shown for driving tracks carrying projecting teeth. This wheel has rim 44 provided with side flanges 45 for engaging the side edges of the track in the same manner as do the flanges of driving wheels but is provided with an intermediate recess 46 in its rim which is connected to the disk of the wheel track and thus the p driving engagement approaches this inner surface of the track and the strain on theteeth mountings, anchor plates 2| and cables |1 is not excessive.

While tracks carrying teeth 31 for cooperating with driving sprockets as above set forth may be preferred in some instances, the tracks provided with tooth contact wear plates 25 have definite advantages over them in that there are no projecting parts on the tracks, except when auxiliary t traction cleats are attached to their tread surfaces, and the met that the drive is in the une tf the center of the track. It will be noted that wear plates 25 are wholly within the body section of the track tread and are engaged to be driven substantially along the line of cables I1, which avoids any tipping action which might result with a tooth on the surface of a track.

While tracks as above described may be made by molding the tread directly around the assembly, it is preferable to rst coat all the parts, steel cables, whether braided or stranded, anchor members and clamps with a thin coat of rubber or rubber compound before placing the assembly in the body of the rubber tread, and then submit the Whole to a nal vulcanization process as described. By the pre-coating process the adhesion of the tread rubber to the parts is assured. When the pre-coating of rubber is thin it has been found that it will receive the required vulcanizing when the main body is vulcanized; however when heavier coatings are required on the parts than can be had with such thin coatings such heavier coatings may be given some pre-vulcanizing. Though the assembly is preferably coated with rubber it may be coated with a self-curing rubber compound or a cement compound which is self-curing when exposed to air, or other forms of plastic material or cement which will provide for the proper adhesion between the parts and the surrounding rubber tread body which is applied thereover.

In Figures 12 and 13 there is shown a modified steel tensioning band consisting of a wide heavy wire braid 54 which is fastened to the anchor plate and driving member 55 instead of a plurality of cables I1 as previously described. In this tensioning band the braid is spread to provide the various openings as indicated at 56. Obviously a plurality of such braided strands can be employed in parallel relationship the same as the cables and then again they may be made up into layers to form cables. It will therefore be understood that these tensioning members as referred to in the claims may comprise a single band such as the wide braid 54, a plurality of narrower braided bands, cables I1, or thelike. These members are essentially flexible for passing around the wheels and of sumcient strength to absorb all the pull or tension required.

In addition to the cored out openings 29 along the central portion of the' track body, as shown in Figure 3, the track may be provided with additional holes 50 for the dissipation of heat. As further shown in Figures 2 and 3, lateral holes 5| extending into the tread body from the sides as shown, or entirely through the tread from side to ventilation to prevent heating at high speeds.

In place of the cleats 39 shown in Figure l0 having widely separated ground gripping members 4| between which dirt passes in passing through the openings 29 in the rubber track body, steel U shaped cleats 51 as shown in Figure 14 may be substituted. Again composition or rubber cleats 58 of the form shown in` Figure 15 may be employed. These cleats are secured in the track grooves and in the anchor members in the manner previously set forth, and being narrower the dirt in the openings passes around theminstead of through them.

Figures 16 and 17 show other types of grooves in the tread face of the rubber track body which as shown may be staggered and not extending all the way across, for example at 59 and 60 as shown, in piace of the transverse grooves shown in Figures 9 and 10. These grooves provide ari tiskid tread surface and also may serve for holding cleats in place which cleats would have to conform with the grooves.

In order to facilitate the adhesion of rubber to the steel track members they may be roughened. As shown in Figures 18 and 19 anchor members 6| may have punched holes 62 for getting better rubber adhesion and both the edges of the plates and the clamp members 63 may 10 be corrugated as indicated. Clamps 63 are each provided with cable slots 64 the lower middle portions 65 of which areformed concave. In assembling plates 6| on cables |1 by means of these clamps 63 a preferably loose wedge piece 66 sepal5 rating the cable from the plate and having a convex profile is inserted in the slot between the cableand plate as shown to depress the cable into the concave portion 65 of the clamp, or if desired the wedge piece may be formed or struck from the platel as an integral part thereof. To clamp the cablesttightly, as shown at the left side of Figure 18, a bolt 61 is inserted through openings 68 while the clamp is welded to plate at 69. Openings 68 afterwards serve for receiving 25 the cleat holding bolts as already described.

Figures 20 and 21 show a slightly diderent form of steel track which is assembled in a modified manner. In this track two or more tread bodies of rubber 10, 1|,etc., are molded separately with 30 holes cored to permit inserting the cables 12 after being cured or vulcanized. These cables 12 have their ends secured in one or more of the anchor members 13, as shown, at the ends of two of the rubber tread body sections.` In addition to the cored openings for cables 12 the tread body sections are provided with'transverse cored slots 14 for receiving the anchor members 13 and cored holes 15 for inserting the various fastening members etc. As shown, the anchor members 13 in- 40 stead of being plates are tubular in form, or they may be any other desired shape. These anchor members 13 are formed in upper and lower halves 13a and 13b providing cable clamps which are secured on oppositesides of cables 12 by rivets or 45 bolts 16 after these members are positioned in the tread body members. These anchor members 13 are provided with holes for receiving cleat holding bolts as previously set forthand while they are adapted to be engaged directly by teeth projecting from a driving Wheel in which case the anchor member itself is the driving member of the track, wear plates or track teeth providing intermediate driving members of the character hereinbefore described may be fastened to them.

IWhile the curved plates 2| are shown in the previously described embodiments they may be replaced by such combined driving and anchor members 13 or other forms within the spirit of my invention. 6 It is obvious that tracks substantially as shown can be applied to excavators and the like for operating the digger buckets, etc., in place of the present chain type belts. o

yThe preferred embodiments of my -invention having been described it is apparent that variations in form may be made within thespirit of my invention and the scope of the claims.

I claimz- 70 l. A flexible band track comprising, a longitudinally extending flexible tensioning member, a plurality'of driving members extending crosswise-of the tensioning member atv intervals, and a plurality of bodies of rubberthrea'ded on' said 75 tensioning member and enveloping said tensioning and driving members.

2. A flexible band track comprising, longitudinally extending exible tensioning members, a plurality of anchor members extending crosswise thereof at intervals, said anchormembers being curved in a lengthwise direction of the tensioning members, and tread body rubber enveloping said tensioning members and anchor members.-

3. A flexible band track comprising, a longitudinally extending flexible tensioning member, a plurality of driving members extending crosswise thereof at intervals, a body of rubber enveloping said tensioning and driving members, said body having a plurality of pairs of laterally extending cushioning projections on its outer face at the intervals of said driving members, a plurality of traction cleats, and means for securing said cleats to said driving members and so as to compress the cushioning projections on the outer surface of the rubber enveloping body where the band is at.

4. A flexible band track comprising, longitudinally extending flexible tensioning members a plurality of driving members extending crosswise thereof at intervals, tread body rubber enveloping said tensioning and driving members, said tread rubber body having a plurality of grooves in its outer surface, a plurality of traction cleats having portions adapted to be seated in said grooves in the outer surface of said body member, and means for securing said cleats against said outer surface of the rubber body and to said driving members.

5. A flexible band track subject to continuous flexing when in operation on a track laying tractor or the like comprising a plurality of longitudinally extending flexible rubber penetrated and covered tensioning members a plurality of rubber covereddriving members extending crosswise thereof at intervals, said crosswise extending members having convex surfaces for engagement with said tensioning members with their edges in the longitudinal directions of the tensioning members normally spaced therefrom for receiving rubber for cushioning the tensioning members, and vulcanized tread body rubber enveloping said rubber covered tensioning and driving members.

6. A flexible band track comprising, the assembly of a plurality of rubber covered cables extending longitudinally of the track and a plurality of rubber covered anchor members at spaced intervals along said cables, a. main rubber tread body over said assembly, intermediate driving members secured to the an-f chor members, by removable members and said main rubber tread body being provided with openings extending outwardly from said securing members for the driving members whereby the driving members may be interchangeable.

7. A flexible band track comprising, the assembly of a plurality of rubber covered cables extending longitudinally of the track and a pluralitl7 of rubber covered anchor members at spaced intervals along said cables, a main rubber tread body over said assembly, said anchor members having pairs of apertures and the main rubber tread is provided with corresponding apertures, traction cleats engaging the outer tread surface of the main rubber tread, each cleat also having a corresponding pair of apertures, and a pair of bolts engaging said anchor members and traction cleats for securing the cleats in position as provided for by said apertures. d

8. A flexible band track which is subject to continuous flexing while in use comprising a exible stranded metal cable longitudinal tensioning 5 member, consisting of a central exible metal strand and outer-flexible metal strands surrounding the central metal strand in engagement therewith but in spaced relationship with respect to each other, .a coating material over said stranded cable and in the space between the outer strands providing a lock for the coating material, members secured crosswise of said tenl.sioning member to provide driving means for the flexible band track, said anchor members l5 having convex surfaces for engagement with said cable with their edges in the longitudinal directions of the cable normally spaced therefrom for receiving rubber for cushioning the cable, and tread body rubber encasing said tensioning member and cross members providing the tread of the flexible band track.

9. A exible band track, including a plurality of longitudinally extending tensioning members, a plurality of anchor members extending crosswise thereof at intervals, and tread body rubber enveloping said members having a longitudinal series of openings therethrough from face to face and intermediate the sides thereof, transversely through which openings said anchor members extend.

10. A flexible band track, including a plurality of longitudinally extending tensioning members, a plurality of anchor members extending crosswise thereof at intervals, and tread body rubber enveloping said members having a longitudinal series of openings therethrough from face to face and intermediate the sides thereof, transversely through which openings said anchor membersextend providing a series of apertures 40 through which dirt may be ejected along each side of each anchor member.

11. A flexible band track, including a plurality of longitudinally extending tensioning members,

a plurality of anchor members extending crosswise thereof at intervals, tread body rubber enveloping said Vmembers having a longitudinal series of openings therethrough from face to face and intermediate the sides thereof at the intervals of said anchor members, and a series of apertures through the anchor members and the body of rubber on oppositeL sides of said openings, cleats adapted to engage the outer face of said tread body rubber each having correspondingopenings and apertures therethrough, and securing means extending through said apertures in the cleats and anchor members for se curing the cleats to the track.

12. A exible band track, including a plurality of longitudinally extending tensioning members, a plurality of anchor members extending crosswise thereof at intervals, tread body rubber enveloping said members having a longitudinal series of openings therethrough from face toface and intermediate the sides thereof at the intervals of said anchor members, and a tooth contact wearing plate engaging each of" said anchor members within said openings through the body of rubber.

13. A flexible band track, including a plurality of longitudinally extending tensioning members,

a plurality of anchor members extending crosswise thereof at intervals, tread body rubber enveloping said members having a longitudinal series of openings therethrough from face to `and a plurality of anchor members at spaced intervals therein, saidrtread body having'openings therein at the intervals of the anchor members, and a tooth contact Wear plate engaging each of said anchor members as provided for by the openings, and means for securing said wear plates to said anchor members.

15. A flexible band track, including a plurality of longitudinally extending tensioning members, a plurality of anchor members extending crosswise thereof at intervals, tread body rubber enveloping said members and having a series of grooves in the tread face thereof at the intervals of said anchor members, cleats having portions adapted to be seated in said grooves, and means for securing said cleats seated in said grooves to said anchor members.

16. A iiexible band track with a tread body of rubber having grooves in the tread face thereof, cleat members seated in said grooves, and means for securing said cleat members seated therein.

17. A exible band track with a tread body of rubber having grooves in the tread face thereof, cleat members having portions seated in said grooves and portions extending beyond the grooves in both lengthwisedirections of the track and engaging corresponding portions of the tread face thereof, and means for securing said cleat members to the track.

18. A iiexible band track with a tread body of rubber having grooves in the tread face thereof, cleat members having portions seated in said grooves, portions extending beyond the grooves in both lengthwise directions of the track and engaging corresponding portions of the tread face thereof and ground gripping portions extending outwardly from the remote ends of the last named portions, and means for securing said cleat members to the track.

19. A flexible band track for track laying tractors and the like which is; subject to continuous flexing while the tractor is moving, including a stranded iiexible metal cable longitudinal tensioning member consisting of a central metal strand and outer metal strands surrounding the central metal strand in engagement therewith but in spaced relationship with respect to each other to provide spaces for the admission of rubber, a series of anchor members at spaced intervals thereon to provide driving means for the track, said anchor members having convex surfaces for engagement with said cable with their edges in the longitudinal directions of the cable normally spaced therefrom for receiving rubber for cushioning the cable, and tread body rubber encasing said members providing the tread of the flexible band track.

20. A exible band track for track laying tractors and the like which is subject to continuous flexing as the tractor moves including rubber covered flexible metal tensioning members, rubber covered anchor members at intervals therealong, said anchor members having convex surfaces for engagement with said tensioning members with their edges inthe longitudinal directions of the tensioning members normally spaced therefrom for receiving rubber for cushioning the tensioning members, and a tread body of rubber encasing and adhering to the surface of the said rubber covered metal members.

21. A iiexible band track for cooperating with a wheel having projecting teeth comprising a plurality of longitudinally extending flexible tensioning members, a plurality of anchor members extending crosswise thereof at intervals, a tooth contact wear plate secured to each of said anchor members in a midway position thereon and having ends which overhang the anchor member, and tread body rubber enveloping said tensioning and anchorv members, said band track having a central longitudinal series of openings between the wear plates on the anchor members for receiving teeth projecting from the wheel which teeth engage the ends of said wear plates in the openings.

22. In a exible rubbercovered` metal band of said anchor members as provided for by the openings, 'and means for securing said driving members to said anchor members.

24. In a iiexible rubber covered metal band track having longitudinally extending tensioning members therein and anchor members extending crosswise on said tensioning members at intervals, removable teeth contacting wear plates engaging the anchor members and having shoulders at their ends which overhang the corresponding end portions of the anchor members.

25. A flexible band track comprising, a plurality of longitudinally extending rubber covered cables or the like, a plurality of driving members having convex surfaces for engagement with said cables and extending crosswise thereof at intervals, means for securing the driving members to the cables without distorting the cables, and tread body rubber enveloping said cables and driving members and filling spaces between the rubber covered cables and driving members to provide cushioning for the cables during the bending movement of the track.

26. A flexible band track comprising, a plurality of longitudinally extending flexible rubber covered tensioning members, a plurality of anchor members having convex surfaces for engagement with said tensioning members and extending crosswise thereof at intervals and secured thereto in a manner so as not to distort the tensioning members, a tooth secured to and vextending inwardly from each of said anchor members, and tread body rubber enveloping said tensioning and anchor members and lling spaces between the rubber covered tensioning members and driving members to provide cushioning for the tensioning members during the bending movements of the track.

27. A flexible band track comprising, a. plurality of longitudinally extending flexible rubber covered tensioning members, a plurality of driving members having convex surfaces for engagement with said tensioning members and extending crosswise thereof at intervals and secured thereto in a manner so as not to distort the tensioning members, tread body rubber enveloping said tensioning and driving members and lling spaces between the rubber. covered tensioning members andv driving members to provide cushioning for the tensioning members during the bending movements of the track, a plurality of traction cleats, and means for securing said cleats against the outer surface of the rubber enveloping body and to said driving members.

V28. A flexible band track comprising, a plurality of longitudinally extending exible rubber covered tensioning members, a plurality of driving members having convex surfaces for engage'- ment with said tensioning members and extending crosswise thereof at intervals and secured thereto in a manner so as not to distort the tensioning members, and tread body rubber enveloping said tensioning and driving members and filling spaces between the rubber covered tensioning members and driving members to provide cushioning for the tensioning members during the bending movement of the track, said tread body rubber having a, plurality of grooves in its outer surface.

29. A rubber covered metal exible band track which is subject to continuous flexing when in use on a track laying tractor or the like, comprisl ing rubber covered iiexible metal tensioning mem- 10 bers, 'rubber covered driving members along said tensioning members at spaced intervals, said driving members having convex surfaces for engagement with said tensioning members with their edges in the longitudinal directions of the ten-,15 sioning members normally spaced therefrom for receiving rubber for cushioning the tensioning members, and surrounding tread body vulcanized rubber in which said rubber covered tensioning members and driving members are embedded.

' EDWARD C. MYERS. 

